1. Field of the Invention
This invention relates to cross-country skiing. More specifically, this invention relates to cross country ski training with a mechanism.
2. Description of Related Art
Cross-country skiers use many different devices to simulate snow when out of season. Three of the most popular devices are roller skis, off-road roller skis, and cross-country exercise machines.
Roller skis usually have one or two wheels mounted at the ends of a narrow member as seen in FIG. 18, U.S. Pat. No. 4,033,596 to Andorson et al., 1977 Jul. 5. They are typically used by more competitive skiers and simulate snow skiing by rolling atop flat outdoor surfaces such as paved roads.
Roller skis are generally very unstable compared to similar devices such as inline skates or roller skates and are dangerous at high speeds. This alone dissuades many recreational skiers and competitive skiers alike from using them. For workouts, they usually can only offer as much resistance as the bearings in the wheels offer and can be difficult and time consuming to replace when a different resistance is wanted. They usually also have soft wheels to absorb road vibration and to control speed which wear out quickly and can be expensive to replace. As the wheels are typically small, they require well-maintained roads which can be hard to locate. When good roads are used, users still have to be careful to avoid any road hazards, such as cracks, pot holes, and loose gravel that catch the small wheels. Most roller skis do not have any means for braking and those that do only reduce speed. That means that when skiing along roads, users have very little control on hills and through intersections. Finally, the most dangerous and negative aspect is that by skiing on roads, roller skiers must be cautious of automobiles while having very little control over their own movements.
Off-road roller skis are similar to conventional roller skis in that they have generally one or two wheels mounted on at the ends of a narrow elongated member. An example of this is U.S. Pat. No. 6,254,113 to Dornan, 2001 Jul. 3, seen in FIG. 19. Although they are minimally used by cross-country skiers, they are generally used by a broader range of skiers than normal roller skis because they do not have to share paths with automobiles and may be used on more surfaces. The wheels on off-road roller skis are generally much larger than normal roller ski wheels and are often pneumatic. This leads to many problems, the first of such being flat tires and wheel blowouts which can strand users during a workout. Furthermore, in an effort to reduce weight, thinner tires are used and therefore are less resistant to wear than a typical solid roller ski wheel. Off-road roller skis are also still limited to fairly smooth paths such as crushed limestone and work poorly on terrains such as sand, gravel or grass. Furthermore, these roller skis are much heavier and therefore harder to control. The greatest problem is that the off-road ski is less stable than customary roller skis because of higher ground clearance and higher center of gravity. Ultimately, this can teach and cause reinforcement of poor and improper skiing technique.
Cross-country exercise machines are used by less experienced skiers and recreational skiers. An illustration of a typical machine is FIG. 20, from U.S. Pat. No. 5,246,412 to Chen, 1993 Sep. 21. They are made to be used indoors and take up a good amount of space. They are also heavy and bulky, requiring many parts and significant frames to support users' weight. All this makes them expensive and limits the number of people who are able to purchase them. They also do not provide an especially accurate simulation of ski technique and can deteriorate a skier's technique. And, they are traditionally limited to a single technique, the diagonal stride. Additionally, they have also been found to cause unnecessary back stress from users leaning forward while pushing and pulling hand levers.